Method of treating oil



Filed sept. 2, 1922 P. W. PRUTZM-AN ET AL METHOD 0F TREATING oILs lase.

Nov. 17I 1925.

l Patented Nov. 17, 1925.

. UNITED STATES PATENT OFFICE.

PAUL W. IPRUTZMAN AND CARL J. von BIBRA. OF LOS ANGELES, CALIFORNIA, AS-

SIGNORS TO GENERAL PETROLEUM CORPORATION, OF LOS ANGELES, CALIFORNIA,

A CORPORATION F CALIFORNIA.

'METHOD oF TREATING oIT..

Application filed September 2, 1922. Serial No. 586,042.

lates tothe art of treating oils generally for the decolorization andremoval of impurities therefrom, and While the invention is adapted forthe treatment of all types of oils the same is more particularlyadapted" for use in connection with 'petroleum lubrieating oilsand theobjects of the invention are to simplify andexpedite the decolorizvationand purification of the oils` and for the production of a material fromminerals of y the mont-morillonite type adapted for'the purposesdesired.

Heretofore it has been customary in 'the treatment of oils with mineraladsorbent solids for the decolorization and purification thereof, tosubject-the mineral to reaction with acid while in a plastic condition,washing the resultant mixture substantially free from the acid andreaction products, draining or filtering the washed mineral to .free thelsame from its Water soluble constituents, drying the mass at anelevated temperature and reducing the dried mass to a powder. When thisdried powder is applied to an oil to v.be decolorized-at a temperaturein excess of 250 F., oxygenis liberated and coacts with the oil to suchan extent as. to produce a darker color in the oil than would have beenobtained if oxygen had not been so liberated. At temperatures lower thanabout 250 F. the air which 'is caused to be occluded in the pores of themineral by dryingv and grinding in contact With the air is, in largepart, retained in the pores of such mineral when same is brought intocontact-with oil at such temperatures, but -at any temperaturematerially higher than 250 F. the occluded air is displaced by the oiland liberated inthe form of microscopic bubbles having a very largecontact surface and a correspondingly great effectiveness as anoxidizing agent.

In the carrying out of our invention for the production of adecolorizing and purifying material, the washed mineral earth is notfreed from Water by draining or filtrationbut by evaporation in Contactwith the oil to be treated, and lWhile maintained out of Contact with.the atmosphere, and the material is employed and utilized forintermixture with the oil to be treated in the form of a mud or plasticmass.

It has been found from practical operation that a decided loss inedectiveness is -suffered by exposingor permitting the eX-l posure ofthe decolorzing and purifying material to air upon the removal of the"wash Water therefrom, which loss in effectiveness in all probabilitylis occasioned by or due to the adsorption of gases and impurities fromthe air, and the loss in effectiveness continues until approximately anequilibrium-is reached and such equilibrium in many cases is aboutone-half 'of the original eiectiveness of the material. Ob-

viously, it is 'extremely advantageous to pref serve orgmaintainavailable the full original effectiveness of the material, and if suchcan be maintained and preserved a smaller quantity vof the decolorizingand purifying material may be utilized in the treatment of" oils thanheretofore required for such pur-l poses, to such an extent materiallyreducing or minimizing the expense of treatment, While at the 'same timethe Work of treatment is'ex edited and labor incident thereto reduce toa minimum.` Under our invention. thesefsavings are made or renderedpossible by allowing'the oil ywhich is to be decolorized and purified tobe brought into intimate contact with the `vsolid particles of the mudor4 plastic mass of the mineral earth as the water contained therein isevaporated from around them and from the interior of the pores withwhich each particle which is so to speak, honeycombed, and in thismanner permitting the full e'ect of the material to be expended on theoil while all other substances are excluded.

- The removal of the Water from the plastic mass or mud is chea er and amuch slmpler process when .broug t about by the quick evaporation in thepresence of the oil to be treated, than when effected by draining orfiltration, followed by relatively slow drying Again, as the oil to betreated 'or under treatment is necessarily brought into intimate contactwith the mud or lastic material, there is no object in providing a dryoil and inasmuchasl the material when acting upon the majority of oilshas the power of removing acids therefrom, there is no necessity for theuse of an alkali for the purpose ofV neutralizing the acid treatment orrather the acid treated oils and such step in the method of treating'theoils is eliminated. In the treatment of the oils the method may be saidto reside in the following steps z-Agitation of the oils with sulphuricacid, removing the finely divided acid sludge and most of the freeacids, intermixing with the oil a decolorizing or purifying agent ormedium formed from mineral earth rendered plastic or placed in muddycondition by the addition of water thereto and when needed preferablytreating with acid as for example sulphuric acid, which mudded massafter the water treatment is permitted to settle for several hours andall clear Water is decanted oil' and the mud, containing approximately85% -of water is run into a mixing tank together with the wet oil. Thetwo substances are then thoroughly intermixed and conveyed to a heaterwhere the temperature is raised for the evaporation of its Watercontents, and the water, together with any light distillates, allowed todistil o We have found that where the mineral earth decolorizing andpurifying medium is utilized in a plastic or mudded form and intermixedwith the oil without exposure to the atmosphere, the oil is brought intomore intimate contact with the surface area of the material than Wherethe earth such as fullers earth adsorbent clays or minerals of themontmorillonite type is previously treated, dried and reduced toy apowdered formin the presence of, or while exposed to the atmosphere withthe result that aquicker and more effective reaction takes place andbetter color to the oil is produced and less of the earth required fortreatment than is necessary under the present methods of decolorizingand purifying lof the oils.

Any suitable form of apparatus may be employed for the carrying out ofthe above described method invention, a simple, practical form ofapparatus for such purpose being illustrated diagrammatically in theaccompanying sheet of drawing and wherein the numeral 1 is employed todesignate a suitable agitator connected with a mixing tank 2, whichreceives the oil from the agitator and with which connects a cooker 3within which the mineral earth is introduced and' placed in plastic ormudded form. From thel-` mixing tank the oil under treatment havingintermixed therewith the plastic or mudded mineral material is deliveredby a pump'4 into a pipe still 5 and 'is' discharged therefrom into anevaporation 6, from which the vapors are conveyed to a` condenser 7.Where this form of an apparatus is employed for treatment, wet oil-stillpartly acid is run from the agitator 1 into the mixing tank 2, theuntreated material of the montmorillonite type preferably is placed inthe cooker '3' and in said cooker is Vrendered plastic by the addition of water and is treated with acid. After being permitted to settle for apredetermined period of time, the excess water is decanted off and themud or plastic mass is then run into the mixing tank while excluded fromcontact with the air and the two mixtures are thoroughly intermixedwithin the said tank and then discharged into the still 5 through theaction of the pump 4 and from the still discharged int-o the evaporatorwhere the pressure is released and the water, together with lightdistillates is distilled off and conveyed to the condenser 7. lf sodesired, Hue gases from the still 5 may be permitted to pass around theevaporator 6 to maintain a temperature in the latter sutliciently highto insure evaporation of all water.

By the use of the expression without exposure to the atmosphere asherein employed, we do not wish to be understood as meaning that themudded or plastic material to be delivered for intermixing with the oilto be treated, shall be housed or protected against exposure to theatmosphere, inasmuch as the water of the mass serves to protect themudded mineral material against contact with the outside atmosphere.said term as we make use thereof in the present case simply means thatthe decolorizing mudded material shall not be brought nor permitted tocome to a condition of dryness prior to being delivered for intermixturewith ,the oil to be treated, but shall be maintained in its mudded formuntil the oil with which it -is intermixed is raised in temperature tosuch a point as will canse the evaporation of the water contents 'of themudded mass. A

By the placing of the'mineral material in the mudded or plastic form, itis obvious that as the same is intermixed with the oil 'durin treatmentfor decolorization the oil is broug tinto contact with what may betermed a film of a decolorizing agent, whereby all available propertiesof the material are utilized for decolorizing and purifying purposes.

It is not our intent to restrict or limit the invention to the use ofany particular type of mineral earth/fin connection with .the treatmentof the oils, but on the contrary we wish to be understood as claimingbroadly 'any other mineral earths capable of employment as adecolorizing and purifying medium when utilized for incorporating or in-The termingling with the oil in a plastic or mudded condition and Whileprotected or main#v tained` from exposure to the atn'iosphere, the Waterof the material being evaporated therefrom under the heatl temperaturesemployed inthe treatment of the oils.

Having thus described our invention what We claim as ne7 and desire toprotect by Letters Patent of the United States, is

i The method of decolorizing-oil which consists in preparing a mass ofpulverulent solid decolorizing material in the form of an aqueouswmud,whereby air is excluded from the pores of the decolorant, miXing suchmud with the oil to be decolorized and 15 rating the spent soliddecolorant fromthe 20 decolorized oil. e.

lIn testimony whereof We have'signed our l names to this specification-`PAUL W. PRUTZMAN. CARL J. voN BIBRA.

